This proposal seeks continued pilot-level support for a biomedical-clinical mass spectrometry research resource for the San Francisco Bay area which would effectively service northern California by virtue of collaborative liaison with clinicians--routinely treating patients in this entire geographical area. It is the expressed purpose of this program to spearhead West Coast exploration of the scope and exploitation of the applications of existing know-how and continually upgraded analytical capabilities of computerized mass spectrometry (both high and low resolution, gas chromatography/high resolution mass spectrometry, chemical ionization, field desorption) and related separation techniques to problem areas of importance to the clinicians of the San Francisco Bay area. The ingredients which are necessary in order to implement the program as envisaged include: 1) mobilization and utilization of core of expertise in existing mass spectrometry group and its augmentation with added biomedically oriented personnel; 2) upgrading of existing mass spectrometry and computer software capability and its tailoring to tractable medical priorities set by advisory committee and Principal Investigator; 3) implementation of a routine mass spectrometry service and accessible interpretative expertise for collaborating clinicians and clinical pathology laboratories; and 4) active program in the dissemination of knowledge of scope and extent of center analytical capabilities into the clinical and biomedical community through an elective medical scientist and M.D. training program. Some of the areas of clinical importance which are being investigated include the study of genetic diseases, the screening of potentially mentally retarded children, screening for inborn errors in metabolism, the detection of cancer prior to clinical symptoms, appraisal of metabolic profiles in physiological fluids and tissue, etc. The use of mass spectrometry emergency diagnosis in drug and toxin overdose cases is of great interest.